This invention relates to the field of mobile robotics and more particularly to coupled robotic vehicles operated in tandem.
Hazardous or hostile conditions have led to a need to minimize or restrict human presence in the hazardous environment. Mobile robots can be used in a first response to environments containing hazardous chemicals, radioactive substances, unexploded ordnance, and other hazards; in hostile adversary situations such as special forces operations, security force responses, bomb neutralizing, search and rescue operations, and adversary surveillance and monitoring; and in accident scenarios in industries such as mining to serve as a quick-response hazards sensor in synergy with an observation platform. When the hazardous environment also imposes requirements for high mobility or obstacle climbing, as well as a need to overcome communication range limitations and communication blackout situations, robotic control systems need to provide an operator with versatile communications and video options for new generations of mobile robots. In addition, the usefulness of a robotic system can be limited by the terrain it can successfully traverse.
Mobile Robot Systems
Vehicles in mobile robot systems come in varying sizes, from small miniature robotic vehicles (for example, vehicles substantially the size of a paperback book), to approximately ⅓-meter long vehicle platforms, to mid-sized 1-meter long platform robotic vehicles, to even human-carrier-sized robotic vehicles. An example wheeled robotic vehicle is a RATLER(trademark), like those developed by Sandia National Laboratories. See Klarer and Purvis, xe2x80x9cA Highly Agile Mobility Chassis Design for a Robotic All-Terrain Lunar Exploration Rover,xe2x80x9d incorporated herein by reference. A robotic vehicle system generally has a robotic vehicle and a system for controlling the robotic vehicle. See Pletta, xe2x80x9cSurveillance and Reconnaissance Ground Equipment (SARGE), Real Robots for Real Soldiers,xe2x80x9d Sandia Report SAND94-0767C, for presentation at the Fifth International Symposium on Robotics and Manufacturing, Aug. 15-17, 1994, in Maui, HI, incorporated herein by reference; and Amai et al., xe2x80x9cRobotic All-Terrain Lunar Exploration Rover (Ratler) FY93 Program Status Report,xe2x80x9d Sandia Report SAND94-1706, October 1994, incorporated herein by reference.
Mobile robotic vehicles have been operated singly or controlled with group operations, with each individual robotic unit receiving similar control commands, but have not been coupled together and synergistically controlled to take advantage of operation in tandem.
Mobile Robot Control Units
When mobile robots are used in field operations, their robotic control units and peripherals preferably are self-contained and easily human-portable. Available power can be limited due to the need to hand-carry all battery power.
Available portable control units can take the form of hand-held boxes (several versions have been developed by Sandia National Laboratories) and can have a suitcase-like appearance or be carried on a neck-strap. See Pletta and Amai et al. With xe2x80x9cbackpack robots,xe2x80x9d both the control units and the mobile robots can be packed and carried by a team of operators to transport the units and robots from position to position.
Computer laptops with added capabilities have been used as control units. Commercially available wearable computers are made by VIA Computers and others. While these computers can be easily portable, they have the capabilities of computers and do not have the integrated capabilities of a control system (for example, reading operator inputs, radio frequency (RF) communications, displaying video from a robot, and other control system capabilities).
There is a need for a robotic vehicle system, of two or more mobile robots working together, that can navigate difficult terrain with high mobility and navigate in closed environments. One example usage is in military special forces"" applications where mobile robots can be used in the field in either a repeater mode to extend the communication distance or overcome communications blackout situations, or in a connected mode to provide advanced terrain navigation mobility, or in individual robot control mode. Another example is in explosive ordnance disposal applications where mobile robots (for example, robotic vehicles) can be used to search for and help remove explosives. Accordingly, there is an unmet need for a robotic vehicle system, with separable units working in synergy, suitable for terrain navigation mobility and coordinated search and rescue operations.
Using two or more mobile robots as either a connected single unit or as individual separated units synergistically working together can meet the need for high mobility is and provide a reduced footprintfor operations in limited spaces. This invention provides a robotic vehicle system suitable for terrain navigation mobility with two or more mobile robots either linked or unlinked and operating together in tandem. A coupling device physically connects the two robots in tandem. The system further comprises a control unit which in its various embodiments, can comprise an input output system with a motion command device and a mode selector, a data transceiver, a video receiver, a video display apparatus, a power source, and a microprocessor.